Interactive terminals and other data devices typically transmit information in intermittent bursts. Packet switching systems, including some local area networks (LAN), enable efficient communications between different data devices, connected together over a data bus, by breaking up the bursty data transmissions into short data packets and by multiplexing together the data packets from several different data devices onto the data bus. The location of a packet switching system is often referred to as a node. When internodal data communication is required, a trunk circuit is utilized to interface the packet nodes to the private or public facilities (trunks) which interconnect the nodes. The design of such trunk circuits or modules for interfacing wideband nodes via low-speed data trunks requires the consideration of the associated queueing delays on the trunk, particularly for interactive data messages. One known arrangement (described in the article entitled "Queueing and Framing Disciplines For a Mixture of Data Traffic Types", authored by A. G. Fraser and S. P. Morgan and published in the AT&T Bell Laboratories Technical Journal, July-August 1984, Vol. 63, No. 6, Part 2) utilizes a queueing discipline whereby short interactive data messages are given priority over longer data messages. That arrangement, however, requires separate data queues for each data channel of the trunk circuit. To keep trunk circuit cost low these queues are implemented in software rather than in hardware circuits.